This is more than an occupational hazard. Technicolor rockets exploded over the crowded San Pablito fireworks bazaar outside Mexico City as a huge blast destroyed 80 percent of the market stalls. Paramedics and police rushed to the scene, where 31 people were killed and another 70 injured, including 13 children who were sent to Texas for medical care. State Governor Eruviel Avila has promised to punish those responsible, but the cause of the blast is not yet known. Meanwhile, investigators are using DNA testing to identify victims’ badly burned bodies.